Automatic cut-off device



J. c. ABl-:1 1,724,389

AUTOMATIC CUT-OFF DEVICE Filed March l5. 1928 2 Sheets-Sheel l Aug. 13, 1929.

Aug. 13, 1929.

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J. c. ABEL AUTOMATIC CUT-OFF DEVICE Filed March 13, 1928 2 Sheets-Sheet 2 cfOSep/ /EZ,

Patented Aug. 13, 13219.,

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JOSEH C, ABEL, GF HOIVITY, OKLAHGMA, ASSGNOR F ONE-RIGHTSy TO THOMAS C. VANDRUFF, ONE-FOURTH TO SGH@ EI. OLEVENGER, NE-'EIGfHT-I TO ARTHUR E.

BURRIS, ONE-EGHTH TO QSEPH H. CGMER, ONE-EIGHTH T0 ELMO ONE-EIGHTH TO MALCO A. NECKEL'L, AND ONE-EIGHTH TO tVlLLlAlVl.'

ALL 0F HOMNY, OKLAHOMA.

L. NIoKnLL, n. scHwABA,

A''TOMATC CUT-OFF DEVICE.'

Application mea March 13, 1928. serial No. 261,312.

This invention relates to a device for automatically shutting oli the supply of gas or the like when the pressure becomes too low.

The primary object of the present invention is to provide a device of the above kind which is extremely sensitive to reduction 'in pressure and positive and certain in action.l

A further object is to provide a device or the above kind which is extremely simple in construction, so as to not readily get out et order7 and to present a device which may be economically manufactured.

ther objects and advantages of the inven- V tion will be set forth in the :following description. l l

The drawings show two embodiments oi the invention in practical form.

Figure 1 is an elevational view of one embodiment of the' invention7 showing the posi- -0 tion ofthe parts when the gas supply is under normal pressure and is passing through the device.

Figure 2 is a central vertical section of the device shown in Figure 1.

Figure 3 is a horizontal section ron line 3 3 of Figure 1. Y

Figure e is a fragmentary elevation look'- ing toward the left of Figure 1, showing the latch bolt and adjacent parts. Figure 5 is a perspective view of the latch bolt.

Figure 6 is a view'similar to Figure lof a further embodiment of the invention. Y

Figure 7 is a View similar-to Figure 2 of the device shown in Figure.

Like reference characters V indicate corresponding parts throughout the several Views.

Each embodiment of the device includes a vertical cylindrical body which is closed at-its upper end by means of a cap 6, and at its lower end by a wall 7.

A central inlet port 8 yis provided' in the bottom wall 7 and in communication with the axial bore of an inlet nipple 9 which is controlled by a turn plug or rotary valve member 10 carried by said nipple, the body 5 having a side outlet port 11 intermediate' its ends and in communication with the axial bore of an outlet nipple 12.

ln installing the vdevice for use, the supply :of the latteris an actuating rod 20 having its .rod let and interposed between the cap 6 and the top of the piston valve 13 as shown clear- G5 ly in Figure 2. However, when the normal pressure is on, it overcomes theaction of the comparatively weak spring 16 and' raises the piston 7alve 13 to the full line vposition or' Figure 2 above the outlet port 11, thereby 70 allowing gas or the like to freely flow through the devicel when the valve 10 is open. Y c

The turn plug or-inlet cut-off valve 10 is provided with a lateral operating handle or lever 17 with which is associated a spring 18 for normally closing said valve 10. Thus far described', the construction of both embodiments of the invention are alike except -that the spring 16 is not used in the e1n- 80 bodiment of the invention shown in Figures 6 and 7. r

Referring nowtothe embodiment of the invention shown in Figuresl to 5 inclusive, f it will be seen Jthat a longitudinalguide'tube 85 19 is rrigidly provided .on the side of the body 5 opposite that atwwhich the'outlet nipple 12 is located, and slidably projecting into the guide tube 19 through the bottom lower end yloosely `connected to the free end of the handle 17 and provided wtha head 21 on'itsupper end7 the spring 18 beingdisposed about the portion of the rod 20 within the tube 19 and interposed between the 95 under side of the head 21 and the bottom of the tubel 19 so as to normally swing the lever 17 upwardly to close the valve v10. A ball-shaped head 22 is provided on the lower end of the rod 2O beneath the lever 17, and the lever 17 is provided with an enlongated Aslot 23 in which the lower end of the rod 20 loosely works. In this way the rod 20 may effectively actuate the valve without binding of the connected parts.

The tube 19 has an opening in the outer side thereof near its lower end, and rigid with and projecting laterally from the outer side of the tube 19 at opposite sides of the said opening is a pair of spaced opposed guide lugs 24 in which a locking bolt 25 1s slidably mounted for horizontal movement. This bolt 25 is adapted to be slid inwardly through the adjacent opening in the side of the tube 19 so as to have its inner end project in the path of the head 21 of the rod 20, whereby the latter is retained in lowered position against the action of the spring 18 to permit the handle or lever 17 to be manually lowered for fitting the valve 10 in its open position, as well as to normally prevent actuation of the lever 17 by the spring 18 for closing the valve 10.

A vertical trip rod 26 is disposed at the outer side of the tube 19 and has its upper end rigidly connected with the upper end of the piston valve rod 14 as at 27. The lower end of the trip rod 26 slidably projects through a slot 28 in the bolt 25, and provided on the outer edge of the trip rod 26 near its lower end is a beveled or wedged surface 29 so disposed that when the pressure becomes so low as to permit the piston valve 13 to lower under the action of the spring 16, the trip rod 26 will lower and cause the beveled edge portion 29 to engage the outer end wall of the slot 28 of the bolt 25, thereby sliding the bolt 25 outwardly and disengagingit from the head 21 of the rod 20. As soon as the bolt 25 is disengaged from the head 21, the rod is released and the spring 18 expands to force the rod 20 upwardly and close the valve 10 through the connections described. It is thus apparent that should the pressure again be raised to normal the gas will be prevented from flowing through the device by the cutoff valve 10 until the latter is manually opened. The device is manually reset by swinging the lever 17 downwardly' so as to open the valve 10 and lower the rod 2() so that when the trip rod 26 is'raised the latch bolt 2.5 may be slid inwardly to overlie the head 21 and retain the parts in the position of Figure 2. As the spring 18 is considerably stronger than the springl, the head 21 will iirmly engage the inner end of the bolt for holding it inwardly against accidental displacement. Moreover, the normal pressure of the gas overcomes the action of the spring 1G and the weight of the piston valve 13 and connected parts so that the trip rod 2t loes not normally tend to lower and urge the bolt 25 outwardly to released position. Y

In view of the above it will be seen that ag long as the gas is under suiiicient lpressure, the piston valve 13 will be supported in the raised position, together with the attached part, the actuating rod 2() being held down to allow the valve 10 to remain open, by reason of the engagement of the latch bolt 25 over the head 21.

Referring to the embodiment of the invention shown in Figures (3 and 7, it will be seen that the spring 18 is in the nature of a tension spring connecting the handle or lever 17 with the part of the body 5 thereabove. It will thus be apparent that the spring- 18'normally tends to contract for swinging the lever 17 outwardly and closing the valve 10. However, in this form of the invention, the valve 10 is provided with a further oppositely projecting handle or lever 30 whose outer or free end is operativelyconnected with the upper end of the piston valve rod 14by means of a link 31. As long as the gas is under suiiicient pressure to overcome the action of the spring 18 and the weight of the piston valve 13, with its attached. parts 14 and 31, said piston valve 13 will be held above the youtlet port 11 with the valve 10 in open position so that the gas may readily flow through the device. However, when a reductionin gas pressure allows the piston valve 13 to lower by reason of its weight and the action of the spring 18, the action of both will be transmitted to the valve 10 by the arms 17 and 30 for positively closing the cut-ofil or inlet valve 10. As the return of lpressure can not effect opening of the valve 10, it is necessary to manually rotate the lever to open position for resetting the device and again permitting the flow of gas when the pressure is raised to normal. By reason of the connecting link 31 between the rod 14 and the lever, the opening of the valve 10 will effect raising of the piston valve 13 above the outlet port 11, and as soon as the valve 10 is opened the pressure acting on the piston valve 13 will hold the parts in the reset position as shown by full lines in Figure 7. v

Minor changes may be made without departing from the spirit and scope of the invention as claimed.

What I claim as new isi 1. An automatic gas cut-off, including a vertical cylindrical casing' having a bottom inlet port and an inlet nipple communicating with vsaid port and provided with a rotary cut-ofi'I valve, said casing further having a side outlet port intermediate its ends, a piston valve slidably mounted in the casing and movable upwardly above the outlet port by the normal gas pressure when the rotary cut-olf valve is opened, yieldable means to lower the piston valve below the outlet port when the pressure within the casing falls below a predetermined point, said piston valve having a rigid guide rod slidably projecting upwardly through the top of the casing, an operating lever for the rotary cut-off valve, an actuating rod loosely connected to the said operating lever and normally spring-pressed upwardly to close said cut-off valve, a latch bolt engageable with the actuating rod to hold it in lowered position against its actuating spring with the cut-olf valve in open position, and a trip rod rigid with the piston valve rod and operatively associatedwvith the latch bolt tor releasing the latter from the actuating rod upon lowering of the piston valve.

2. An automatic gas cut-oft'7 including a closed casing having a bottom inlet port and an intermediate side outlet port, a piston valve slidably fitted in said casing and movable above and below the outlet port,

an inlet nipple having a bore communicating with the inlet port and provided with a rotary cut-ofil valve having an operating lever, a guide on the side of the casing, an actuating rod loosely connected to the operating lever oi' the cut-off valve and movable vertically in said guide, yieldable means acting to urge the actuating rod upwardly, a locking bolt slidably mounted for movement transversely of the guide into and out of the path of the upper end ot' said actuating rod, and a trip rod connected with the piston valve for retracting the locking bolt upon lowering of the piston valve below the outlet port when the pressure within the casing falls below a predetermined point.

3. An automatic gas cut-oil, including a able vertically in said guide, yieldable means acting to urge the actuating rod upwardly, aI locking bolt slidably mounted for movement transversely of the guide into and out of the path of the upper end of said actuating rod, and a trip rod connected with the piston valve for retracting the locking bolt upon lowering of the piston valve below the outlet port when the pressure within the casing falls below a predetermined point, saidl guide having a pair of spaced lateral guide lugs in which the locking blolt is slidably mounted, and said trip rod having its lower end slidable through the locking bolt and provided with a beveled edge engageable with the latter for moving it to v released position.

4. A device as set forth in claim yl, wherein said trip rod slidably projects through the latch bolt and has a beveled edgey for engagement with the latch bolt to retract the latter when said trip rod lowers with the piston valve.

In testimony whereof I aHX my signature.

JOSEPH C. ABEL. 

